Cloning CentOS Guests - Disable MAC
Today I was scratching my head trying to figure out why my changes to the network to go from DHCP to static IP was not taking effect on my CentOS 7 guest. It turns out that the network configuration is defaulted to including the HWADDR (MAC) address as shown below:
# Generated by dracut initrd NAME="eth0" HWADDR=52:54:00:4D:24:AA ONBOOT=yes NETBOOT=yes UUID="dd66e666-87dc-4814-a862-61b8411c2c3d" IPV6INIT=yes BOOTPROTO=dhcp TYPE=Ethernet DEFROUTE=yes IPV4_FAILURE_FATAL=no IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_FAILURE_FATAL=no PEERDNS=yes PEERROUTES=yes IPV6_PEERDNS=yes IPV6_PEERROUTES=yes
When you clone a guest, the new guest is given a new MAC address but your network scripts will not be automatically updated. If your guests only have 1 NIC then you can just comment the
HWADDR line out and your guests will still work. Thus you can keep cloning without having to remember to update the MAC.